#dict

#Create
#键对值赋值
c = {}
c["a"] = 1
print(c)


#update
t = {"c": 4, "b": 5}
c.update(t)
print(c)


#setdefault
c.setdefault("x", 4)
print(c)




#Retrieve
#键对值访问
print(c["x"])


#get
print(c.get("c"))


#keys()
print(c.keys())
print(list(c.keys()))


#Values()
print(list(c.values()))


#items()
print(list(c.items()))


#Update
c["x"] = 55
print(c)
c.update({"x": 45, "c": 88, "nn": 909})
print(c)


#Delete
#pop
c.pop("x")
print(c)


#popitem()
c.popitem()
print(c)


